Competition bicycles and the like are stripped of weight as much as possible, and metals and other materials of low molecular weight are employed in the various components thereof. The front and rear hub assemblies are of particular concern, and these assemblies are among those components made of light weight metals such as aluminum, comprised of forged and turned parts of tubular configuration. A typical racing hub is illustrated in this disclosure, together with what I will term a "High Strength Light Weight Bike Axle" characterized by a tensioning member that pre-loads the anti-friction bearings through the application of inner nuts, and by mounting sleeves extending between said inner nuts and outer clamp members. The mounting sleeves are received by the forks of the bike frame, and the threads on the tensioning member are protected. It is a primary object of this invention to provide increased strength in a bike axle at the bearing engagement of the frame forks therewith, whereby light weight metals of reduced dimension can be employed to replace heavier metals of ordinary greater dimension.
Heretofore, heavy steel axles, washers and nuts have been relied upon for clamping bike hubs in their operating positions. This procedure applies to peddle powered bicycles and to motorcycles as well, as follows: The frame forks of the vehicles have been bifurcated for a loose fit, and the clamping force applied by the outer nut relied upon for positioning the hub in this placement of the axle. This loose fit concept of the axle within a fork slot induces bending of the axle, is subject to slipping, and it has required heavy construction using high strength metals such as carbon steels and the like. It is an object of this invention to provide a bearing or mounting member which can be fitted into a fork slot to accept shear forces, whereby bending moments transmitted into the axle tensioning member are reduced and substantially eliminated. With the present invention, the supporting loads of the vehicle are localized as shear loads between the forks of the vehicle frame and the mounting sleeves that I provide.
It is an object of this invention to transfer loads in shear through a sleeve, loads applied directly between the vehicle fork and hub bearing. In place of a "through-axle" per se, I provide the tensioning member that carries the inner nuts to pre-load the antifriction bearings. The tension member also threadedly receives the clamp member or screw fastener therefor, as the case may be. The mounting sleeve is carried by either the inner nut or outer clamp member and is stabilized when the clamp member is tightened; in shear with the fork and with the antifriction bearings.
It is also an object of this invention to prevent shifting of the rear axle assembly when subjected to severe strains, selective positioning blocks being provided to maintain axle assembly position at the rear forks.